1. Field of the Invention
This invention relates to the field of spindle mounting apparatus, particularly in magnetic data storage disk systems.
2. Statement of the Problem
In magnetic disk drives, the disks are supported on a spindle within a disk drive housing. These spindles are rotatably driven by either an internally mounted motor or an externally mounted motor having a shaft attached to the disk spindle. The disks are driven at relatively high rates of speed with magnetic read/write heads moving radially across the disk for reading or recording data at selective locations on the disks. In disk drives, the relative positioning between the heads and disk requires great precision. This precision can be affected by thermal distortion, by vibration, as well as other factors.
Typically, the spindles are mounted on bearings in the disk drive housings which are attached by screws to bearing caps. The bearing caps, in turn, are attached to the drive housing by screws. This assembly normally requires up to 16 screws to securely attach each end of the spindle to the drive housing.
The use of screws creates several problems. During installation in a clean room environment, mounting with screws can result in particle contamination which can affect the performance of the assembled disk drive.
Further, the use of screws generate inconsistent loading of the spindle. The only reliable procedure of testing the loading of the screws is by gauging the torque on the screws. However, this is affected by the friction of the screws, misalignment with the pilot holes, and other factors. The loading of the spindle is critical, for if the load is too small, the spindle can slip with respect to the base during usage due to temperature cycling, vibration, or shock, causing the hard disk assembly to fail. The attachment by screws also increases the cost of assembly of the disk drive.
Therefore, there exists a need for a spindle clamping arrangement that will reduce the need for screws, reduce the potential for particle contamination, and provide a simpler procedure of assembly that will provide a uniform loading on the spindle.
3. Solution to the Problem
The present invention solves these problems and others by providing a mount to quickly assemble the spindle in a housing without the need for a large number of screws.
The present invention further provides a pre-loaded clamping arrangement applying a consistent and uniform load on the spindle.
The present invention provides a seal to protect the bearings and inner housing from contamination.
These and other solutions will become evident from the following descriptions and drawings.